Sheet package

ABSTRACT

A sheet package includes a packaging bag that accommodates a plurality of sheets that are stacked, and a retrieval opening that opens in a top surface of the packaging bag. Perforations are provided in the top surface. The perforations surround a region of a portion of the top surface, and form the retrieval opening upon the perforations being torn. A tab is provided in the region.

TECHNICAL FIELD

The present invention relates to a sheet package.

BACKGROUND ART

For hygienic thin paper such as tissue paper, a carton-type sheetpackage, in which the hygienic thin paper is accommodated by a cardboardbox, is common, but in recent years, the demand for a soft pack-typesheet package, in which the hygienic thin paper is accommodated by afilm packaging bag, has increased from the viewpoint of transportation,storage, disposal, environmental load, cost, and the like. In the softpack-type sheet package, a retrieval opening (an opening formed uponperforations or the like being torn) for retrieving a sheet is providedon a top surface of a packaging bag (see, for example, Patent Documents1 and 2).

RELATED ART DOCUMENTS Patent Document

[Patent Document 1] Japanese Laid-Open Patent Publication No.2008-183034

[Patent Document 2] Japanese Laid-Open Patent Publication No.2018-177364

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

It is an object of the present invention to provide a sheet package thatfacilitates the formation of a retrieval opening.

Means for Solving Problem

A first embodiment of the present invention is a sheet package includinga packaging bag accommodating a plurality of sheets that are stacked anda retrieval opening to open in a top surface of the packaging bag.Perforations are provided in the top surface. The perforations surrounda region of a portion of the top surface and form the retrieval openingupon the perforations being torn. A tab is provided in the region.

Effects of the Invention

According to an aspect of the present invention, a sheet package thatfacilitates the formation of a retrieval opening can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a sheet package according to an embodiment;

FIG. 2 is a drawing of the sheet package of FIG. 1, viewed from above;FIG. 3 is a drawing illustrating a retrieval opening and a tab in thesheet package of FIG. 1;

FIG. 4 is an enlarged view of the tab of FIG. 3;

FIG. 5 is a drawing of the tab of FIG. 4 viewed in the Z direction;

FIG. 6 is a drawing of the tab of FIG. 4 viewed in the Y direction;

FIG. 7 is a drawing in which the retrieval opening opens in the sheetpackage of FIG. 1;

FIG. 8 is a drawing illustrating a broken fragment produced after theretrieval opening opens in the sheet package of FIG. 1;

FIG. 9 is a drawing illustrating a conventional sheet package (aretrieval opening formed of a linear slit); and

FIG. 10 is a drawing illustrating a conventional sheet package (aretrieval opening formed of an elliptical slit).

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described in detail withreference to the drawings. Here, portions common to respective drawingsmay be denoted by the same reference numerals and description thereofmay be omitted. Additionally, in each drawing, the scale of each membermay differ from the actual scale.

In the present specification, a three-dimensional orthogonal coordinatesystem in three axis directions (the X direction, the Y direction, andthe Z direction) is used to set the longitudinal direction or the leftand right direction (hereinafter referred to as a first direction) ofthe sheet package as the X direction, the transverse direction or thedepth direction (hereinafter referred to as a second direction) as the Ydirection, and the height direction or the up and down direction as theZ direction. Additionally, “above” indicates the upper side of the topsurface of the packaging bag in the height direction (the Z direction)of the sheet package.

FIG. 1 is a drawing illustrating a sheet package according to anembodiment. FIG. 2 is a drawing of the sheet package of FIG. 1, viewedfrom above, and FIG. 3 is a drawing illustrating a retrieval opening anda tab in the sheet package of FIG. 1. FIG. 4 is an enlarged drawing ofthe tab of

FIG. 3, FIG. 5 is a drawing of the tab of FIG. 4, viewed in the Zdirection, and FIG. 6 is a drawing of the tab of FIG. 4, viewed in the Ydirection. FIG. 7 is a drawing in which the retrieval opening opens inthe sheet package of FIG. 1. FIG. 8 is a drawing illustrating a brokenfragment produced after the retrieval opening opens in the sheet packageof FIG. 1.

A sheet package 100 according to the present embodiment includes apackaging bag 10 and a retrieval opening 20, as illustrated in FIG. 1.The sheet package 100 is an example of a sheet package according to thepresent invention. Additionally, the packaging bag 10 is an example of apackaging bag forming the sheet package according to the presentinvention, and the retrieval opening 20 is an example of a retrievalopening formed in the packaging bag.

The packaging bag 10 accommodates multiple (or multiple sets of) sheetsS that are stacked (hereinafter referred to as a sheet stack SL) asillustrated in FIG. 1. The sheet stack SL is accommodated in thepackaging bag 10 such that a stacking direction (the SD direction) ofthe sheet S is in the height direction (the Z direction). The sheetstack SL is configured such that one sheet S (or a set of sheets S) canbe pulled out at one time through retrieval opening 20 (an opening OP)formed in the packaging bag 10 (see FIG. 7).

The form of the sheet stack SL is not particularly limited and includes,for example, a stack in which respective sheets S are folded and arealternately stacked (what is called a pop-up sheet stack SL), a stack inwhich multiple (or multiple sets of) sheets S are simply stacked, and astack in which respective sheets S are folded and stacked. Here, fromthe viewpoint of pulling out one sheet S or one set thereof, it ispreferable that the form of the sheet stack SL is a pop-up sheet stackSL.

Additionally, the dimensions of the sheet stack SL may be as follows:the length of the sheet package 100 in the first direction (the Xdirection) is 80 mm or greater and 250 mm or less, the length of thesheet package 100 in the depth direction (the Y direction) orthogonal tothe first direction (the X direction) is 50 mm or greater and 130 mm orless, and the height in the height direction (the Z direction) is 10 mmor greater and 90 mm or less. Such a sheet stack may be fabricated, forexample, by rotary or multi-stand inter folder.

The use of the sheet S is not particularly limited and is applicable tohygienic thin paper, such as tissue paper, toilet paper, kitchen paper,a paper towel, and the like. These hygienic thin paper may also includehygienic thin paper containing a moisturizing component (e.g., a lotiontissue). Additionally, the use of hygienic thin paper forming the sheetS is not particularly limited, and is applicable to any of industrial,household, and portable use. Here, the sheet package 100 according tothe present embodiment is preferably used for household tissue amongthese.

The ply number of the sheet S may be one ply or greater, preferably oneply, and more preferably two-ply (two-sheet stack). Additionally, theshape of the sheet S is not particularly limited. For example, itispreferable that a shape in which two-ply sheets are folded isrectangular in plan view.

A material of the sheet S is not particularly limited. For example, asheet, such as paper, non-woven fabric, or cloth can be used. Preferablya sheet of paper (hereinafter referred to as a paper sheet) is used.Here, when the sheet S is a paper sheet, a raw paper made mainly frompulp is used. For the pulp composition, any known composition in thepaper sheet can be used. For example, the composition ratio of pulp maybe 50% by mass or greater, preferably 90% by mass or greater, and morepreferably 100% by mass.

Additionally, the pulp composition of the sheet S (the paper sheet) isnot particularly limited. For example, a softwood pulp such as needlebleached kraft pulp (NBKP) or needle unbleached kraft pulp (NUKP) and ahardwood pulp such as leaf bleached kraft pulp (LBKP) or leaf unbleachedkraft pulp (LUKP) can be used in any ratio. .Here, the ratio of softwoodpulp to hardwood pulp is not limited, but is preferably 10:90 to 80:20,more preferably, a pulp composition in which a ratio of softwood pulp tohardwood pulp is higher. Additionally, for the pulp contained in thesheet S (the paper sheet), used paper pulp may be used.

The basis weight of the sheet S is not particularly limited, but,depending on the ply number, the basis weight of the sheet S ispreferably 5 g/m² or greater and 80 g/m² or less for paper, and 20 g/m²or greater and 100 g/m² or less for non-woven fabric. Here, the basisweight can be measured in accordance with JIS P 8124.

Additionally, the thickness of the sheet S (the paper sheet) is notparticularly limited, and the paper thickness measured in theenvironment of JIS P 8111 (1998) can be used. For example, the paperthickness of the paper sheet forming the sheet S may be 50 μm or greaterand 500 μm or less per 2-ply, and preferably 60 μm or greater and 330 μmor less per 2-ply.

Additionally, the sheet S (the paper sheet) may be embossed. Suchembossing can be performed by using a publicly known embossing method.

The packaging form of the packaging bag 10 is not particularly limited.In the present embodiment, for example, packaging in which both ends ofa cylindrical flexible film are folded and sealed (caramel packaging),packaging in which both ends or either end of a cylindrical flexiblefilm is folded in a gusset and sealed (pillow packaging), packaging inwhich heat-shrinkable resin film is heated to adhere to an object to bepackaged (shrink packaging), or any combination thereof can be used.

In the present embodiment, the sheet stack SL packaged by caramelpackaging. Specifically, side surfaces 15 and 16 of the packaging bag 10are folded and sealed. Thus, a sealed portion 30 is formed on the sidesurface 15 of the packaging bag 10, and a sealed portion 40 is formed onthe side surface 16 (see FIG. 1).

In such caramel packaging, the sheet stack SL is wrapped by a flexiblefilm to be rolled in a cylindrical shape such that both ends of thesheet stack SL in the longitudinal direction (in the X direction) areopen, and overlapped portions of the flexible film in the rollingdirection are bonded together by a fusion process or an adhesive. Bothends of the cylindrical flexible film in the longitudinal direction (theX direction) are folded toward both side surfaces of the sheet stack SL,and at least leading edges of a substantially triangular or trapezoidalportion formed by the folding are overlapped and bonded together by afusion process or an adhesive to seal respective openings of thecylindrical flexible film (see FIG. 1).

Additionally, the material of the flexible film forming the packagingbag 10 is not particularly limited. For example, a resin, such aspolyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET),polystyrene (PS), polyvinyl chloride (PVC), ethylene-vinyl acetatecopolymer (EVA), and polyamide (PA) can be used.

Here, among these flexible films, polyethylene, polypropylene,polyethylene terephthalate, and the like are preferable from theviewpoint of flexibility and excellent handling, high sealing propertywhen heat-sealed, low cost, and the like. Additionally, polyethylene ispreferable from the viewpoint that polyethylene is odorless, hasexcellent water resistance and chemical resistance, can be mass-producedat a low cost, and the like. As polyethylene, high-density polyethylene,low-density polyethylene, or the like can be used. Additionally,polypropylene is preferable from the viewpoint that polypropylene isrobust, easy to mold, achieves good color development at the time ofprinting, can impart gloss, and the like.

The form of the flexible film forming the packaging bag 10 is notparticularly limited and may be a single layer film in which theabove-described resin is formed as a single layer, a laminated film inwhich the above-described resin is laminated, or a mixed film in which amixture of two or more of the above-described resins is formed.

The thickness of the flexible film forming the packaging bag 10 is notparticularly limited, and is preferably 20 μm or greater and 100 μm orless, more preferably 25 μm or greater and 70 μm or less. When thethickness of the flexible film is 20 μm or greater, sufficient strengthas the packaging bag 10 accommodating the sheet S can be obtained.Additionally, when the thickness of the flexible film is 100 μm or lessin thickness, flexibility and lightness of the packaging bag 10 can beobtained, and cost can be reduced.

Here, the material forming the packaging bag 10 is not limited to aresin material such as the flexible film described above, and a papermaterial may be used. Additionally, as the material forming thepackaging bag 10, a biodegradable material (biodegradable plastic,biodegradable paper, and the like) or a biomass material (an organicresource derived from a renewable organism such as a biomass film,excluding a fossil resource) can be used.

The packaging bag 10 has a top surface 11, a bottom surface 12, a frontsurface 13, a back surface 14, the side surface 15, and the side surface16. In the sheet package 100, the top surface 11 and the bottom surface12 are opposed in the up and down direction (in the Z direction), thefront surface 13 and the back surface 14 are opposed in the front andback direction (in the Y direction), and the side surface 15 and theside surface 16 are opposed in the left and right direction (in the Xdirection). The side surface 15 and the side surface 16 are continuousto the top surface 11, the bottom surface 12, the front surface 13, andthe back surface 14 (see FIG. 1).

The retrieval opening 20 is formed to be open in the top surface 11 ofthe packaging bag 10: Specifically, the retrieval opening 20 correspondsto a region R of a portion of the top surface 11 and is disposed at acenter 11A of the top surface 11 of the packaging bag 10 in the firstdirection (the X direction) of the sheet package 100 and at a center 11Bof the top surface 11 of the packaging bag 10 in the second direction(the Y direction) (see FIG. 1 and FIG. 2). Here, the portion of the topsurface 11 indicates a portion (a portion corresponding to the region R)less than half of the top surface 11.

In the present embodiment, on the top surface 11, perforations Msurrounding the region R of the portion of the top surface 11 areprovided, so that when. the perforations M are torn, the retrievalopening 20 opens (see FIGS. 1 to 3 and 7). Here, the perforations Mindicate a cutting line to be torn in which a cut C and a tie T (anuncut portion between two cuts C) are alternately arranged, and when thetie T is torn, the cuts C on both sides become a continuous cut (seeFIGS. 1 to 3).

The region R surrounded by the perforations M (hereinafter referred toas a perforation region R) has a given length L2 extending in the firstdirection (in the X direction) and a given width W2 expanding in thesecond direction (in the Y direction) intersecting the first direction(the X direction).

Here, the first direction (the X direction) indicates a direction alonga predetermined one direction on the top surface 11 of the packaging bag(the longitudinal direction or the left and right direction of the sheetpackage 100). Additionally, the second direction (the Y direction)intersecting the first direction (the X direction) indicates a directionorthogonal to or diagonally intersecting the direction along thepredetermined one direction on the top surface 11 of the packaging bag10 (the transverse direction or the depth direction of the sheet package100).

Here, in the first direction (the X direction), the dimension of theretrieval opening 20 (the length L2 of the perforation region R) can besuitably determined in accordance with the capacity of the packaging bag10 and the dimensions of the sheet S. For example, with respect to thewidth (the length L1) of the top surface 11 of the packaging bag 10accommodating the sheet S, the length L2 of the perforation region R maybe 100% or less, preferably 5% or greater and 80% or less, and morepreferably 10% or greater and 75% or less (see FIG. 2).

Additionally, in the second direction (the Y direction), the dimensionof the retrieval opening (the width W2 of the perforation region R) canbe suitably determined in accordance with the capacity of the packagingbag 10 and the dimensions of the sheet S. For example; with respect tothe length (the width W1) of the top surface 11 of the packaging bag 10,the width W2 of the perforation region R may be 1% or greater and 25% orless, preferably 3% or greater and 20% or less, more preferably 5% orgreater and 15% or less (see FIG. 2).

The perforation region R includes a base 21 and ends 22 and 23 (see FIG.2 and FIG. 3). The base 21 is a substantially rectangular region orrange that is present between two linear perforations M1 opposing eachother in the transverse direction (the Y direction) of the sheet package100 and that extends substantially parallel to the longitudinaldirection (the X direction) of the sheet package 100. Here, theperforations M1 forming the base 21 of the perforation region R areperforations in which the cut C1 and the tie T1 are alternately arranged(see FIG. 3).

The ends 22 and 23 are continuous to ends 21A and 21B of the base 21 andare dumbbell-shaped regions or ranges that are surrounded. byeggplant-shaped. perforations M2 and M3 and the ends 21A and 21B of thebase 21, respectively. Here, the perforations M2 forming the ends 22 and23 of the perforation region R are perforations in which a cut C2 and atie T2 are alternately arranged (see FIG. 3).

Here, in the second direction (the Y direction), the dimension of theretrieval opening 20 (the width W3 of the perforation region R) can besuitably determined in accordance with the capacity of the packaging bag10 and the dimensions of the sheet S. For example, relative to thelength (the width W1) of the top surface 11 of the packaging bag 10, thewidth W3 of the perforation region R may be 5% or greater and 35% orless, preferably 10% or greater and 30% or less, and more preferably 15%or greater and 25% or less (see FIG. 2).

Here, the width of the base 21 in the second direction (the Y direction)corresponds to the width W2 of the above-described perforation region R(see FIG. 2). Additionally, the maximum width of the ends 22 and 23 inthe second direction (the Y direction) corresponds to the width W3 ofthe perforation region R (see FIG. 2).

The length of the cut C1 and the length of the tie T1 in theperforations M1 forming the base 21 of the perforation region R aresuitably determined. The length of each cut C1 may be 0.8 mm or greaterand 5 mm or less, preferably 1.5 mm or greater and 4.5 mm or less, andmore preferably 2.5 mm or greater and 4 mm or less. The length of eachtie T1 may be 0.3 mm or greater and 5 mm or less, preferably 0.4 mm orgreater and 2 mm or less, and more preferably 0.5 mm or greater and 1.5mm or less.

The length of the cut C2 and the length of the tie T2 in theperforations M2 and M3 forming the ends 22 and 23 of the perforationregion R are suitably determined. The length of each cut C2 may be 0.8mm or greater and 5 mm or less, preferably 1.5 mm or greater and 4.5 mmor less, and more preferably 2.5 mm or greater and 4 mm or less. Thelength of each tie T2 may be 0.3 mm or greater and 5 mm or less,preferably 0.4 mm or greater and 2 mm or less, and more preferably 0.5mm or greater and 1.5 mm or less.

The perforation region R has such a shape, so that the width W2 isnarrowed from both ends 22 and 23 of the region R in the first direction(the X direction) toward the center 24 of the region R. Specifically,the perforation region R has the width W2 of the region R in the seconddirection (the Y direction) widened from the center 24 in the firstdirection (the X direction) toward both ends 22 and 23. That is, at bothends 22 and 23 of the perforation region R, the width W2 is expanded tothe width W3 (see FIGS. 1 to 3).

Additionally, in the present embodiment, the linear perforations M1forming the base 21 of the perforation region R are edges E1 and E2 ofthe perforation region R opposing each other in the second direction(the Y direction). Additionally, portions of the eggplant-shapedperforations M2 and M3 respectively forming the ends 22 and 23 of theperforation region R correspond to the edges E3 and E4 of theperforation region R opposing each other in the first direction (the Xdirection) (see FIG. 3).

In the present embodiment, both edges E3 and E4 of the perforationregion R in the first direction (the X direction) have an arc shape thatis convex to the outer region OR of the region R. Here, the term “havean arc shape that is convex” indicates that each of the edges E3 and E4is convexly curved.

In the present embodiment, portions of the perforations M2 forming bothedges E3 and E4 of the perforation region R are formed of two cuts C2having an arc shape, and two cuts C2 are connected through one tie T2(see FIG. 3).

Here, the shape of the perforations M2 forming both edges E3 and E4 ofthe perforation region R is not limited to the present embodiment.

For example, a portion of the perforations M2 forming both edges E3 andE4 may be formed of three cuts C2 having an arc shape and two ties T2connecting two adjacent cuts C2. Additionally, a portion of theperforations M2 forming both edges E3 and E4 may be formed of one cut C2and no tie T2.

In the sheet package 100 of the present embodiment, a tab 50 is providedin the perforation region R (see FIGS. 1 to 6). Here, the tab 50indicates a portion or member that is pinched by tips of fingers or thelike. In the present embodiment, the tab 50 is formed as a memberseparate from the. packaging bag 10 (see FIGS. 1 to 6).

The material of the tab 50 is not limited. A resin material, a papermaterial, a biodegradable material, a biomass material, or the like,which are materials of the flexible film (the film F illustrated inFIGS. 4 to 6) or the like used in the above-described packaging bag 10,can be used. Additionally, the form of the tab 50 is not limited, and asingle layer film, a laminated film, or a mixed film used for theabove-described packaging bag 10 can be used. Further, the thickness oftab 50 may employ the thickness of the flexible film used in theabove-described packaging bag 10.

In the present embodiment, the tab 50 is provided on at least one end ofthe, perforation region R in the first direction (the X direction).Here, one end of the region R in the first direction (the X direction)indicates one of the ends (the end 22 or the end 23) of the perforationregion R in the first direction (the X direction). In the presentembodiment, the tab 50 is provided on the end 23 of the perforationregion R.

The tab 50 includes a bonded portion 51 and a non-bonded portion 52. Thebonded portion 51 is a portion that is bonded to the perforation regionR. The non-bonded portion 52 is a portion that is not bonded to theregion R.

In the present embodiment, the tab 50 includes the bonded portion 51that has a substantially rectangular shape and the non-bonded portion 52that has a bow shape. Specifically, the non-bonded portion 52 isadjacent to the bonded portion 51 such that one side of the rectangularshape that forms the bonded portion 51 overlaps a chord of the bow shape(a line joining the ends of the arc) that forms the non-bonded portion52 (see FIG. 4 and FIG. 5). Here, in the present embodiment, a portionof the perforations M3 forming the edge E4 of the perforation region Ris entirely covered by the bonded portion 51 of the tab 50 (FIG. 2 andFIG. 3).

In the tab 50, the area ratio of the bonded portion 51 to the non-bondedportion 52 is not limited, but preferably the area ratio of the bondedportion 51 to the non-bonded portion 52 is 4:1 to 8:1, and morepreferably 5:1 to 7:1 (see FIG. 5). Here, the area ratio represents theratio of the area of the bonded portion 51 to the area of the non-bondedportion 52.

In the present embodiment, an adhesive layer 51A is provided on a side,of the bonded portion 51, facing the perforation region R (a surface ofthe bonded portion 51 viewed in the Z direction) (see FIG. 5 and FIG.6). A material of the adhesive layer 51A is not particularly limited,but a material that causes the adhesive force of the bonded portion 51to be greater than or equal to 2 N/25 mm and less than or equal to 6N/25 mm is preferable. Here, the “adhesive force” indicates the peelresistance measured by the adhesive force test method referring to JIS20237.

An adhesive may be used as a material having such an adhesive force.Examples of such an adhesive include an adhesive such as rubber-basedadhesives, acrylic-based adhesives, silicone-based adhesives, andurethane-based adhesives. Among these, the acrylic adhesive ispreferable from the viewpoint of reduced deterioration and reduceddiscoloration over time and the like.

Here, preferably, these adhesives contain a curing agent. Examples ofthe curing agent'include isocyanate-based curing agents, epoxy-basedcuring agents, aziridine-based curing agents, metal chelate-based curingagents, and carbodiimide-based curing agents. Among these, theisocyanate-based curing agent used as a curing agent for an acrylicpressure sensitive adhesive is preferable.

Additionally, these adhesives preferably include a crosslinking agent.Examples of the crosslinking agent include epoxy-based crosslinkingagents, isocyanate-based crosslinking agents, amine-based crosslinkingagents, melamine-based crosslinking agents, aziridine-based crosslinkingagents, aldehyde-based crosslinking agents, metal chelate-basedcrosslinking agents, acid anhydride-based crosslinking agents, and thelike. Among these, the epoxy-based crosslinking agent used as acrosslinking agent for the acrylic pressure sensitive adhesive ispreferable.

In the present embodiment, the adhesive layer 51A is formed in thebonded portion 51 by applying such an adhesive to the entirety of thetab 50 including the non-bonded portion 52 and then covering a portioncorresponding to the non-bonded portion 52 with a film, by performingprinting, or the like. Here, a method of forming the adhesive layer 51Ain the bonded portion 51 is not limited thereto. For example, such anadhesive may be applied to the bonded portion 51 of the tab 50 to formthe adhesive layer 51A.

The shape of the non-bonded portion 52 of the tab 50 is not limited, buta free end 52A having an arc shape is preferably included (see FIGS. 1to 6). Here, the free end 52A indicates that the edge 52A of thenon-bonded portion 52 is not fixed.

The tab 50 is not limited to a form in which the entirety of the bondedportion 51 is bonded to the inner region IR of the region R. That is, aportion 51B of the bonded portion 51 may be bonded to an outer region ORof the region R (see FIGS. 1 to 3). Here, the portion 51B of the bondedportion 51 indicates a portion in a range less than half of the bondedportion 51.

In the present embodiment, as described above, the tab 50 is provided ona portion of the top surface 11 surrounded by the perforations M (theperforation region) R, so that when the tab 50 is pinched and pulled up,the perforations M tear thereby generating a fragment B to which the tab50 is attached (see FIG. 7 and FIG. 8).

As illustrated in FIG. 7, this allows the retrieval opening 20 to openat a portion of the top surface 11 that corresponds to the perforationregion R (the opening OP can be formed in the top surface 11 of thepackaging bag 10). As described, according to the present embodiment,the sheet package 100 that facilitates the formation of the retrievalopening 20 (the opening OP) can be obtained.

In the present embodiment, as described above, the tab 50 includes thebonded portion 51 that is bonded to the perforation region R and thenon-bonded portion 52 that is not bonded to the perforation region R, sothat the non-bonded portion 52 of the tab 50 can be pinched with tips offingers while the bonded portion 51 of the tab 50 is fixed to theperforation region R (the inner region IR). Therefore, according to thepresent embodiment, the tab 50 is easily pinched and pulled.

In the present embodiment, as described above, by using the tab 50 inwhich the ratio of the area of the bonded portion 51 to the area of thenon-bonded portion 52 is within the above-described range, the tab 50 ismore easily pinched and pulled up while a state in which the tab 50fixed to the perforation region R (the inner region IR) is maintained.

In the present embodiment, as described above, the configuration inwhich the portion 51B of the bonded portion 51 of the tab 50 is bondedto the outer region OR of the perforation region R is allowed, so thatthe operation of attaching the tab 50 is facilitated when the tab 50 isattached to the packaging bag 10 as a separate member duringmanufacturing of the sheet package 100.

Additionally, in the present embodiment, a portion in the range greaterthan half of the bonded portion 51 is fixed to the perforation region R(the inner region IR), so that when the tab 50 is pinched and pulled up,the perforations M are torn while the tab 50 is fixed to the perforationregion R (the inner region IR), and then the portion 51B of the bondedportion 51 that is bonded to the outer region OR of the perforationregion R is peeled. Therefore, in the present embodiment, the retrievalopening 20 can open in the top surface 11 even though the portion 51B ofthe bonded portion 51 is bonded to the outer region OR of theperforation region R.

In the present embodiment, as described above, the tab 50 having thebonded portion 51 having an adhesive force of 2 N/25 mm or greater and 6N/25 mm or less is provided in the perforation region R, so that theperforations M can be torn when the tab 50 is pinched and pulled upwhile the tab 50 is fixed to the perforation region R (the inner regionIR). This allows the retrieval opening 20 to be easily opened in thepresent embodiment.

Additionally, in the present embodiment, even when the portion 51B ofthe bonded portion 51 is bonded to the outer region OR of theperforation region R, the perforations M are torn while the tab 50 isbonded to the inner region IR of the perforation region R, and then theportion 51B of the bonded portion 51 bonded to the outer region OR ofthe perforation region R can be peeled. In the present embodiment, thisallows the retrieval opening 20 to be easily opened even when theportion 51B of the bonded portion 51 is bonded to the outer region OR ofthe perforation region R (see FIGS. 1 to 3).

In the present embodiment, as described above, the non-bonded portion 52of the tab 50 has the free end 52A having an arc shape, so that the tab50 is even more easily pinched and pulled up.

In the present embodiment, as described above, by having the givenlength L2 extending in the first direction (the X direction) and thegiven width W2 expanding in the second direction (the Y direction)intersecting the first direction (the X direction), the contour shape ofthe perforation region R becomes a long and thin shape with the firstdirection (the X direction) being the longitudinal direction and thesecond direction (the Y direction) being the transverse direction.Additionally, the tab 50 is provided on at least one end (the end 23) ofthe perforation region R in the first direction (the X direction), sothat the tab 50 is easily pulled along the first direction (the Xdirection) toward the other end (the end 22).

Additionally, in the present embodiment, when the tab 50 is pulled alongthe first direction (the X direction) toward the other end (the end 22),the retrieval opening 20 having a thin and long shape corresponding tothe perforation region R can open upon the perforation M being torn.This can form the retrieval opening 20 in which the sheet S is noteasily stuck and the surrounding area of which is not easily broken, onthe top surface 11. Therefore, according to the present embodiment, thesheet package 100 having an excellent retrieval property of the sheet isobtained.

Additionally, according to the present embodiment, the tab 50 isprovided on the end 23 of the perforation region R so as to cover aportion of the perforations M2 forming the edge E4 of the perforationregion R with the bonded portion 51, so that the end 23 of theperforation region. R is unlikely to fold back from the cut C2 of theperforations M2. This prevents the perforations M from being torn duringmanufacturing or sale of the sheet package.

In the present embodiment, as described above, the width of theperforation region R narrows from both ends 22 and 23 in the firstdirection (the X direction) toward the center 24, so that when the tab50 provided at the end 23 of the perforation region R in thelongitudinal direction is pinched and pulled toward the center 24, theperforations M are easily torn from the end 23 in the longitudinaldirection toward the center 24. This facilitates the formation of theretrieval opening 20 in the present embodiment.

Additionally, in the present embodiment, the width of the retrievalopening 20 that opens in the top surface 11 is wider at both ends 22 and23 than that at the center 24 of the retrieval opening 20. Therefore, atboth ends 22 and 23 of the retrieval opening 20, in which the sheet S iseasily stuck and easily broken when the sheet S is pulled out, the sheetS is not easily stuck, and thus breakage of the sheet S can besuppressed. With this configuration, the sheet package 100 having a moreexcellent retrieval property can be obtained in the present embodiment.

In the present embodiment, as described. above, both edges E3 and E4 inthe first direction (the X direction) have an arc shape that is convexto the outer region OR of the perforation region R, so that when the tab50 is pinched and pulled up, the end edge E4 at the end 23 of theperforation region R in the longitudinal direction at which the tab 50is provided is easily torn. Additionally, the edge E3 at the end 22 ofthe perforation region R in the longitudinal direction at which the tab50 is not provided is also easily torn. This further facilitates theformation of the retrieval opening 20 in the present embodiment.

Additionally, in the present embodiment, both edges E3 and E4 of theretrieval opening 20 that opens in the top surface 11 in thelongitudinal direction can be curved toward the outside of the retrievalopening 20. Therefore, at both ends 22 and 23 of the retrieval opening20 in which the sheet S is easily stuck and easily broken when the sheetS is pulled out, the rubbing of the sheet S is reduced. This furthercauses the sheet S not to be easily stuck and suppresses breakage of thesheet S. As described, in the present embodiment, the sheet package 100having a more excellent retrieval property can be obtained.

EXAMPLE

In the following, the present invention will be described specificallywith reference to examples. The following tests were used to evaluatethe Examples, Comparative examples, and Experimental examples.

Sheet Package (Test Sample)

As a test sample, the sheet package 100 (see FIG. 1), in which the sheetstack SL having multiple sheets S stacked therein was accommodated inthe packaging bag 10, was prepared. In the sheet stack SL, tissue paper(the basis weight: 12 g/m²; the paper thickness: 130 μm; the ply number:2-ply; the number of sets: 120 sets (240 sheets); the dimensions: about40 mm in height, about 178 mm in width, about 100 mm in length) stackedsuch that the sheets S are alternately folded to allow each of the setscan be pulled out in a pop-up manner (see FIG. 7). The sheet stack SLwas accommodated in the packaging bag 10 such that the stack direction(the SD direction) was in the height direction (Z direction) of thesheet package 100 (see FIG. 1). As the material of the packaging bag 10,polyethylene (PE) having a 60 μm thick and the surface of which wasmat-finished was used. As the packaging form of the packaging bag 10,caramel packaging was used to seal both side surfaces 15 and 16 of thesheet package 100 (the sealed portions 30 and 40 were formed). Thedimensions of the packaging bag 10 were about 180 mm of the length L1 inthe first direction (the X direction), about 100 mm of the width W1 inthe depth direction (the Y direction), and about 40 mm in height in theheight direction (the Z direction). In the top surface 11 of thepackaging bag 10, the perforations M were formed such that the retrievalopening 20 opens upon the perforations M being torn.

Openability

As the openability of the sheet package (the test sample), the ease ofopening the packaging bag 10 was evaluated when the perforations Mformed in the top surface 11 of the packaging bag 10 were torn to formthe retrieval opening 20 (the opening OP). The evaluation of theopenability was performed according to the following criteria, Oindicates good; and Δ and X indicate poor.

O: The perforations were smoothly torn without placing. a finger on theperforations.Δ: A finger could be placed on the perforations, but the perforationswere not easily torn:X: A finger could not be easily placed on the perforations and theperforations were not easily torn.

Retrieval Property

As the retrieval property of the sheet package (the test sample), theease of retrieval was evaluated when a first set of the sheets S of thesheet stack SL is retrieved from the sheet stack SL accommodated in thepackaging bag 10 of the sheet package 100 through the retrieval opening20 (the opening OP) that opens in the packaging bag 10. The evaluationof the retrieval property was performed according to the followingcriteria, O indicates good, and Δ and X indicate poor.

O: The first set was easily pinched.Δ: The first set could be pinched.X: The first set could be pinched, but could not be easily pinched.

Sheet Breakage

As the sheet breakage of the sheet stack SL, the sheet breakage wasevaluated when the sheets S from the first set to the fifth set of thesheet stack SL are retrieved through the retrieval opening 20 (theopening OP) that opens in the packaging bag 10 from the sheet stack SLaccommodated in the packaging bag 10 of the sheet package 100. Theevaluation of the retrieval property was performed according to thefollowing criteria, O indicates good, and Δ and X indicate poor.

O: No sheets broke.Δ: The first set of sheets broke.X: Two or more sets of sheets broke.

Label (Test Sample)

As a test sample corresponding to the tab, a label (a 50 μm thick PETfilm), on which an adhesive was applied, was prepared.

Adhesive Force

As the adhesive force of the tab (the test sample), by the adhesiveforce measurement method in accordance with JIS 20237, after the testsample (adjusted to a width of 25 mm and a length of 300 mm) was appliedto an object to be covered (a polyethylene film, a stainless steel plate(SUS), and a polyethylene film with a mat-finished surface), areciprocating pressure bonding was performed with a 2 kg pressureroller, and then after the test sample was left for 20 minutes and for24 hours, the resistance value was measured when the applied test samplewas peeled from the object to be covered at a speed of 0.3 m/min in adirection of 180° by using a desktop precision universal testing machine(Autograph AGS-500NG, manufactured by SHIMADZU CORPORATION). The unit ofthe adhesive force is N/25 mm. As the evaluation of the adhesive force,the range of 2 to 6 N/25 mm is good, and anything outside of the rangeis poor.

Peel Force

As the peel force of the tab (the test sample), with respect to the testsample (adjusted to a width of 50 mm and a length of 300 mm), theresistance value was measured in substantially the same way as theabove-described measurement of the adhesive force (an object to becovered is only a polyethylene film and only after the object to becovered is left for 20 minutes) by the adhesive force measurement methodin accordance with JIS 20237 to obtain the peel force (low speed). As inthe above-described measurement of the adhesive force, after the testsample was applied to the object to be covered (the polyethylene film),a high-speed peel tester (TE-701, manufactured by TESTER SANGYO, CO.,Ltd.) was used to measure the resistance when the applied test samplewas peeled from the object to be covered at a speed of 0.3 m/min in thedirection of 180 degrees to obtain the peel force (low speed) and tomeasure the resistance when the applied test sample was peeled at aspeed of 60 m/min to obtain the peel force (high speed). The unit of thepeel force is mN/50 mm. As the evaluation of the peel force (low speed),the range of 120 to 200 mN/50 mm is good, and anything outside of therange is poor. As the evaluation of the peel force (high speed), therange of 450 to 600 mN/50 mm is good, and anything outside of the rangeis poor.

Ball Tack

As a ball tack for the tab (test sample), the test sample (adjusted to awidth of 100 mm and a length of 150 mm) was placed on a sloped surfacewith an angle of 30° such that the surface on which an adhesive isapplied (the adhesive surface) faces up, steel balls having differentdiameters were caused to roll through a 100 mm runway, and the maximumdiameter of the steel balls stopped on the adhesive surface was measuredby the J. DOW method in accordance with JIS 20237. A higher valuerepresents a higher tack, and as a rough indication of the size, 1 inchsteel ball is No. 32. For example, No. 4 indicates a steel ball of 4/32inch in size. As the evaluation of the ball tack, the range of No. 12 to15 is good, and anything outside of the range is poor.

Label Peeling

As label peeling, it was checked whether the label was peeled away afterthe label (the test sample) was attached to the object to be covered(glassine paper) and then the label was left for 20 minutes and for 24hours. The evaluation of label peeling was performed according to thefollowing criteria, O indicates good, and Δ and X indicate poor.

O: The label did not peel away.Δ: The label peeled away.X: The label peeled before 20 minutes passed.

Package Film Stretch and Breakage

As a breakage of the package film, it was checked whether the object tobe covered (the package film) corresponding to the packaging bag isstretched and broken when the label was peeled from the object to becovered (the package film) after the label (the test sample) was appliedto the object to be covered (polyethylene the surface of which wasmat-finished) and then the object to be covered was left for 20 minutesand for 24 hours. The evaluation of the stretch and breakage of thepackage film was performed according to the following criteria, Oindicates good, and Δ and X indicate poor.

O: The object did not become stretched and did not break.Δ: The object did not break, but became stretched.X: The object broke.

Breakage of Perforations

As a breakage of the perforations, breakage of the perforations M wasevaluated when the label was peeled after the label was bonded to theend 23 of the perforation region R of the sheet package 100 and then thesheet package 100 was left for 24 hours. The evaluation of breakage ofthe perforations was performed according to the following criteria, Oindicates good, and A and X indicate poor.

O: The perforations broke.Δ: The perforations broke, but the outside of the perforation regionalso broke.X: The perforations did not break.

Sensory Property (Ease of Opening After 24 Hours)

As a sensory property, the ease of opening was evaluated after the labelwas bonded, as the tab, to the end 23 of the perforation region R of thesheet package 100 and then the sheet package 100 was left for 24 hours.The evaluation of the sensory property was performed according to thefollowing criteria, 3 or greater indicates good, and 2 or less indicatespoor.

5: Very easy to open4: Easy to open3: Can be opened2: Slightly difficult to open1: Difficult to open

In the following, Examples, Comparative examples, and Experimentalexamples will be described.

Example 1

With respect to the sheet package 100 (see FIGS. 1 to 6), in which theregion R of the portion, of the top surface 11 of the packaging bag 10,corresponding to the retrieval opening 20 is surrounded by theperforations M (perforations M1, M2, and M3), both ends 22 and 23 of theperforation region R are widened from the center 24 in the firstdirection (in the X direction) toward both ends 22 and 23, the tab 50 isprovided at the end 23 of the perforation region R having an arc shape(a dumbbell shape) in which both edges E3 and E4 of the perforationregion R in the first direction (the X direction) are convex to theouter region OR of the region R, and the portion 51B of the bondedportion 51 of the tab 50 is bonded to the outer region OR of theperforation region R, the openability, the retrieval property, and thesheet breakage were evaluated. The results are shown in Table 1.

Comparative Example 1

Except that the retrieval opening 20 was formed by only a linear slit(the perforations M4) (see FIG. 9), the evaluation was performed as inExample 1. The results are shown in Table 1.

Comparative Example 2

Except that the retrieval opening 20 was formed by only a substantiallyelliptical slit (the perforations M5) (see FIG. 10), the evaluation wasperformed as in Example 1. The results are shown in Table 1.

Experimental Example 1

With respect to a test sample to which an acrylic-based adhesive(containing an isocyanate-based curing agent of 0.3% and an epoxy-basedcrosslinking agent) is applied as an adhesive, the adhesive force, thepeel force, the ball tack, the label peeling, the stretch and breakageof the package film, breakage of the perforations, and the sensoryproperty were evaluated. The results are shown in Table 2. Here, thecondition of Experimental example 1 corresponds to the condition of thetab 50 of the sheet package 100 (the test sample) of Example 1.

Experimental Example 2

Except that the contained amount of the isocyanate-based curing agent inthe acrylic-based adhesive is 0.5%, as an adhesive, the evaluation wasperformed as in Experimental example 1. The results are shown in Table1.

Experimental Example 3

Except that the contained amount of the isocyanate-based curing agent inthe acrylic-based adhesive is 2.4% and the isocyanate-based crosslinkingagent is used instead of the epoxy-based crosslinking agent, as anadhesive, the evaluation was performed as in Experimental example 1. Theresults are shown in Table 1.

Experimental Example 4

Except that the contained amount of the isocyanate-based curing agent inthe acrylic-based adhesive is 3.5%, as an adhesive, the evaluation wasperformed as in Experimental example 3. The results are shown in Table1.

Experimental Example 5

Except that the contained amount of the isocyanate-based curing agent inthe acrylic-based adhesive is 3.9%, as an adhesive, the evaluation wasperformed as in Experimental example 3. The results are shown in Table1.

TABLE 1 COMPARATIVE COMPARATIVE EXAMPLE 1 EXAMPLE 1 EXAMPLE 2 RETRIEVALPERFORATIONS DUMBBELL TYPE LINEAR TYPE ELLIPTICAL TYPE OPENING TAB END —— EVALUATION OPENABILITY ◯ Δ X RETRIEVAL ◯ X ◯ PROPERTY SHEET ◯ X ◯BREAKAGE

TABLE 2 EXPERI- EXPERI- EXPERI- EXPERI- EXPERI- MENTAL MENTAL MENTALMENTAL MENTAL EXAMPLE 1 EXAMPLE 2 EXAMPLE 3 EXAMPLE 4 EXAMPLE 5 ADHESIVEPE AFTER 20 MINUTES 2.8 0.9 8.1 6.9 6.5 FORCE AFTER 24 HOURS 4 1.5 9 7.97.6 (N/25 mm) SUS AFTER 20 MINUTES 4.1 1.4 14.9 12.3 11.8 AFTER 24 HOURS4.7 1.9 16.8 14.5 13.8 MAT AFTER 20 MINUTES 3.0 1.0 9.6 8.9 8.2 FINISHEDAFTER 24 HOURS 4.1 1.8 12.4 10.9 10.3 PE PEEL FORCE LOW SPEED (0.3m/min) 127 112 78 73 70 (mN/50 mm) HIGH SPEED (60 m/min) 499 374 412 411397 BALL TACK (No.) 13 10 4 4 3 PERFORMANCE AFTER LABEL IS PEELED ◯ Δ ◯◯ ◯ EVALUATION 20 MINUTES OR NOT PACKAGE FILM IS ◯ ◯ ◯ ◯ ◯STRETCHED/BROKEN OR NOT AFTER LABEL IS PEELED ◯ ◯ ◯ ◯ ◯ 24 HOURS OR NOTPACKAGE FILM IS ◯ ◯ Δ Δ Δ STRETCHED/BROKEN OR NOT BREAKAGE OFPERFORATIONS ◯ X ◯ ◯ ◯ SENSORY PROPERTY 5 4 1 2 2 (EASE OF OPENING AFTER24 HOURS)

According to Table 1, the sheet package 100, in which both ends 22 and23 are widened from the center 24 in the first direction (the Xdirection) toward both ends 22 and 23, and the tab 50 is provided at theend 23 of the perforation region R having a circular arc shape in whichboth edges E3 and E4 in the first direction (the X direction) are convexto the outer region OR of the region R was excellent in each of theopenability, the retrieval property, and the sheet breakage (Example 1).

With respect to the above, the retrieval opening 20 of the slit havingthe linear shape (the perforations M4) is poor in the openablity, theretrieval property, and breakage of the sheet (Comparative example 1).Additionally, the sheet package 100 formed with the substantiallyelliptical slit (the perforations M5) is poor in the openability(Comparative example 2).

According to Table 2, the label on which the acrylic-based adhesive(containing 0.3% of an isocyanate-based curing agent, and an epoxy-basedcrosslinking agent) was applied as an adhesive was good in the adhesiveforce, the peel force, the ball tack, the label peeling, the stretch andbreakage of the package film, breakage of the perforations, and thesensory property (Experimental example 1).

With respect to the above, the label, on which the acrylic-basedadhesive (containing an isocyanate-based curing agent of 0.5% and anepoxy-based crosslinking agent) was applied as an adhesive, was poor in“label is peeled or not after 20 minutes” and breakage of theperforations (Experimental example 2). Additionally, the label on whichthe acrylic-based adhesive (containing an isocyanate-based curing agentof 2.4% and an isocyanate-based crosslinking agent) was applied as anadhesive, the label on which the acrylic-based adhesive (containing anisocyanate-based curing agent of 3.5% and an isocyanate-basedcrosslinking agent) was applied as an adhesive, and the label on whichthe acrylic adhesive (containing an isocyanate-based curing agent of3.9% and an isocyanate-based crosslinking agent) was applied as anadhesive, are poor in “package film is broken after 24 hours” and thesensory property (Experimental Examples 3 to 5).

From these results, it is found that, in the sheet package, in which theperforations that surround the region of the portion of the top surfaceand that form the retrieval opening upon being torn, are provided on thetop surface of the packaging bag and the tag is provided on the region,the retrieval opening is easily formed. Additionally, it is also foundthat, in the sheet package with such a tab including the bonded portionthat is bonded to the region and the non-bonded portion that is notbonded to the region, the tab is easily pinched and easily pulled up.

While the embodiments of the invention have been described, theinvention is not limited to particular embodiments, and variousmodifications and variations can be made within the scope of theinvention as claimed.

In the following, preferred embodiments of the present invention will beappended.

A first embodiment of the present invention is a sheet package includinga packaging bag accommodating multiple sheets that are stacked and aretrieval opening to open in a top surface of the packaging bag.Perforations that surround a region of a portion of the top surface andthat form the retrieval opening upon being torn is provided in the topsurface. A tab is provided on the region.

In the present specification, the portion of the top surface indicates aportion in a range less than half of the top surface. The perforationsindicate a cutting line to be torn in which a cut and a tie (an uncutpart between the two cuts) are alternately arranged, and the twoadjacent cuts become a continuous cut when the tie is broken. The tabindicates a portion or a member that is pinched by tips of fingers orthe like.

In the first embodiment, the tab is provided in the region of theportion of the top surface that is surrounded by the perforations(hereinafter may be referred to as the perforation region), so that theperforations are torn by pinching and pulling up the tab to allow theretrieval opening to open at a portion of the top surface correspondingto the perforation region. Therefore, according to the first embodiment,a sheet package that facilitates the formation of the retrieval openingcan be provided.

A second embodiment of the invention is a sheet package in which the tabincludes the bonded portion that is bonded to the region and thenon-bonded portion that is not bonded to the region. In the secondembodiment, the tab includes the bonded portion that is bonded theperforation region and the non-bonded portion that is not bonded to theperforation region, so that the non-bonded portion of the tab can bepinched with tips of fingers while the bonded portion of the tab isfixed to the perforation region. Therefore, according to the secondembodiment, the tab is easily pinched and easily pulled up.

A third embodiment of the invention is a sheet package in which an arearatio of the bonded portion of the tab to the non-bonded portion of thetab is 4:1 to 8:1. Here, the area ratio is a ratio of the area of thebonded portion to the area of the non-bonded portion. In the thirdembodiment, the area ratio of the bonded portion to the non-bondedportion is set to such a range of the area ratio, so that the tab ismore easily pinched and more easily pulled up while a state, in whichthe tab is fixed to the perforation region, is maintained.

A fourth embodiment of the invention is a sheet package in which aportion of the bonded portion is bonded to the outside of the region.

Here, the portion of the bonded portion indicates a portion in a rangeless than half of the bonded portion. In the fourth embodiment, allowinga configuration in which the portion of the bonded portion of the tab isbonded to the outside of the perforation region facilitates anattachment operation of the tab when the tab is attached to thepackaging bag as a separate member during manufacturing of the sheetpackage.

Additionally, in the fourth embodiment, a portion of the area that isgreater than half of the bonded region is fixed to the perforationregion, so that when the tab is pinched and pulled up, the perforationsare torn with the tab being fixed to the perforation region, and theportion of the bonded portion that is bonded to the outside of theperforation region is peeled. Therefore, in the fourth embodiment, eventhough the portion of the bonded portion is bonded to the outside of theperforation region, the retrieval opening can be opened in the topsurface.

A fifth embodiment of the present invention is a sheet package in whichthe adhesive force of the bonded portion is 2 N/25 mm or greater and 6N/25 mm or less. Here, the adhesive force indicates a peel resistancevalue measured by the adhesive force test method in reference to JIS20237.

In the fifth embodiment, a tab having a bonded portion having anadhesive force of 2 N/25 mm or greater and 6 N/25 mm or less is providedin the perforation area, so that when the tab is pinched and pulled. up,the perforations can be torn while the tab is fixed to the perforationregion. This allows the retrieval opening to be easily opened in thefifth embodiment.

Additionally, in the fifth embodiment, even when the portion of thebonded portion is bonded to the outside of the perforation region, theperforations are torn while the tab is bonded to the inside of theperforation region, and the portion of the bonded portion that is bondedto the outside of the perforation region can be peeled. This allows theretrieval opening to be easily opened in the fifth embodiment, even whenthe portion of the bonded portion is bonded to the outside of theperforation region.

A sixth embodiment of the invention is a sheet package in which thenon-bonded portion has a free end having an arc shape. Here, the freeend indicates that an edge of the non-bonded portion is not fixed. Inthe sixth embodiment, the non-bonded portion of the tab has the free endhaving the arc shape, so that the tab is still more easily pinched andstill more easily pulled up.

A seventh embodiment of the invention is a sheet package in which theregion has a given length extending in the first direction and a givenwidth expanding in the second direction intersecting the firstdirection, and the tab is provided at at least one end of the region inthe first direction.

In the present specification, the first direction indicates a directionalong a predetermined direction on the top surface of the packaging bag.The second direction intersecting the first direction indicates adirection orthogonal to or diagonally intersecting the predetermineddirection on the top surface of the packaging bag. The end of the regionin the first direction indicates either end of the perforation region inthe first direction.

In a seventh embodiment, the contour shape of the perforation region hasa given length extending in the first direction and a given widthexpanding in the second direction intersecting the first direction, sothat the contour shape becomes a thin and long shape having the firstdirection as the longitudinal direction and the second direction as thetransverse direction. Additionally, the tab is provided at least one endof the perforation region in the first direction, so that the tab iseasily pulled along the first direction toward the other end.

Additionally, in the seventh embodiment, when the tab is pulled alongthe first direction toward the other end, the retrieval opening having athin and long shape corresponding to the perforation region can openupon the perforations being torn. This can form, in the top surface, theretrieval opening in which the sheet is not easily stuck and thesurrounding area of which is not easily broken. Therefore, according tothe seventh embodiment, a sheet package having an excellent retrievalproperty can be obtained.

An eighth embodiment according to the present invention is a sheetpackage in which the width of the region narrows from both ends of theregion in the first direction toward the center of the region. Here,“the width narrows from both ends of the region in the first directiontoward the center of the region” indicates that the width of theperforation region in the second direction widens from the center in thefirst direction to both ends.

In the eighth embodiment, the width of the perforation region narrowsfrom both ends to the center side in the first direction, so that whenthe tab provided at the end of the perforation region in thelongitudinal direction is pinched and pulled toward the center in thefirst direction, the perforations are easily torn from the end to thecenter in the longitudinal direction. This facilitates the formation ofthe retrieval opening in the eighth embodiment.

Additionally, in the eighth embodiment, the width of the retrievalopening that opens in the top surface is wider at both ends of theretrieval opening than that at the center of the retrieval opening.Therefore, at both ends of the retrieval opening where the sheet iseasily stuck and easily broken when pulling out the sheet, the sheet isnot easily stuck, and thus breakage of the sheet can be suppressed.Therefore, in the eighth embodiment, a sheet package having betterretrieval property can be obtained.

A ninth embodiment according to the present invention is a sheet packagein which both edges of the region in the first direction have an arcshape that is convex to the outside of the region. Here, both edges ofthe region in the first direction indicate respective edges opposingeach other in the first direction of the perforation region. “have anarc shape that is convex” indicates that each edge is convexly curved.

In the ninth embodiment, both edges in the first direction have an arcshape that is convex to the outside of the perforation region, so thatwhen the tab is pulled up, the edge of the end, at which the tab isprovided, of the perforation region in the longitudinal direction iseasily torn. Additionally, the edge of the end, at which the tab is notprovided, of the perforation region in the longitudinal direction iseasily torn. This further facilitates the formation of the retrievalopening in the ninth embodiment.

Additionally, in the ninth embodiment, both edges, in the longitudinaldirection, of the retrieval opening that opens in the top surface can becurved toward the outside of the retrieval opening. Therefore, at bothends of the retrieval opening where the sheet is easily stuck and easilybroken when the sheet is pulled out, the rubbing of the sheet isreduced. This can cause the sheet not to be easily stuck and cansuppress breakage of the sheet. Therefore, in the ninth embodiment, asheet package having much better retrieval property is obtained.

The present application is based on and claims priority to JapanesePatent Application No. 2020-015212, filed Jan. 31, 2020, the entirety ofwhich is incorporated herein by reference.

DESCRIPTION OF THE REFERENCE NUMERALS

-   100 sheet package-   S sheet (hygienic thin paper)-   SL sheet stack-   10 packaging bag-   11 top surface-   11A center in the first direction-   11B center in the second direction-   12 bottom surface-   13 front surface-   14 back surface-   15, 16 side surface-   20 retrieval opening-   R region-   IR inner region-   OR outer region-   M, M1, M2, M3, M4, M5 perforations-   C, C1, C2 cut-   T, T1, T2 tie-   21 base-   22, 23 end-   24 center-   30 sealed portion-   40 sealed portion-   50 tab-   51 bonded, portion-   51A adhesive layer-   51B portion-   52 non-bonded portion-   52A free end-   L1, L2 length-   W1, W2, W3 width-   OP opening-   E1, E2, E3, E4 edge-   B fragment

1. A sheet package comprising: a packaging bag that accommodates aplurality of sheets, the plurality of sheets being stacked; and aretrieval opening that opens in a top surface of the packaging bag;wherein perforations are provided in the top surface, the perforationssurrounding a region of a portion of the top surface and forming theretrieval opening upon the perforations being torn, and wherein a tab isprovided in the region.
 2. The sheet package as claimed in claim 1,wherein the tab includes a bonded portion and a non-bonded portion, thebonded portion being bonded to the region, and the non-bonded portionbeing not bonded to the region.
 3. The sheet package as claimed in claim2, wherein, in the tab, an area ratio of the bonded portion to thenon-bonded portion is 4:1 to 8:1.
 4. The sheet package as claimed inclaim 2, wherein a portion of the bonded portion is bonded to an outsideof the region.
 5. The sheet package as claimed in claim 2, wherein anadhesive force of the bonded portion is 2 N/25 mm or greater and 6 N/25mm or less.
 6. The sheet package as claimed in claim 2, wherein thenon-bonded portion includes a free end having an arc shape.
 7. The sheetpackage as claimed in claim 1, wherein the region has a given lengthextending in a first direction and a given width expanding in a seconddirection intersecting the first direction, and wherein at least one endof the region in the first direction is provided with the tab.
 8. Thesheet package as claimed in claim 7, wherein the width of the regionnarrows from both ends of the region in the first direction toward acenter of the region in the first direction.
 9. The sheet package asclaimed in claim 7, wherein, in the region, both edges of the region inthe first direction have an arc shape that is convex to an outside ofthe region.